The mentioned photos are located atBefore the introduction of the Y-8 based "high new" specialized surveillance birds in the early 2000s,
the PLAAF operated a small fleet of 4 locally modified Tu-154 for electronic intelligence activities across the Taiwan strait.
Now with a more capable "high new" military airframe in full swing, the PLAAF brass might feel more comfortable in decommissioning those ad hoc Russian airliners.
http://china-defense.blogspot.nl/2013/0 ... elint.html